In a forest estate outside of Belfast, two girls walk towards a witch's hut. The hems of their dresses drag in the mud, because this is Northern Ireland in July and it's drizzling rain. Nevertheless the two girls soldier on. They pause outside the door to the wood-and-thatch hut. It looks freaky, as do most huts in the middle of forests. The two girls walk through the door...

Day 77: From the bottom of a quarry, our VFX supervisor looks up at the ridge above us and shakes his head. As we all shiver in 4°C shadow, he's praying the sun won't rise over the ridge and bathe us in its loving warmth. Because we have some serious VFX elements in this scene and shadows are much easier to match than light. For VFX, hell isn't other people – it's the sunlight on their faces.

Day 64: As the poet says, stone walls do not a prison make. Nowhere is this truer than television. We may write a scene with a character held in a tiny cell, but actual production has its own demands. Whenever you see a character onscreen, know that – just out of sight, behind the camera, off the edge of frame – lurk dozens of crew. And monitors. And cameras. And myriad other equipment without which there could be no show.

Day 15: Who knew scorpions could be stubborn little critters? Not me and not the other hundred crew members who stood patiently holding our breaths as, take after take, our little scorpion actor refused to go in the right direction.

Day 52: Today we film in beautiful Murlough Bay. We're shooting on a rock-strewn beach. The jagged coast of Scotland beckons 11 miles in the distance, across a blue sea. Everything is set for a gorgeous day on GoT...

Yet, as the saying goes, time and tide wait for no man. On the North Coast in autumn, not only don't they wait, they rush in like dry land is going out of style.